Rampaging Rutidosis – a FOG visit* to Crace Nature Reserve and its Button Wrinklewort

In northern Canberra, if you drive towards Mitchell along the Gungahlin Drive Extension (GDE) freeway, or towards Watson along the Barton Highway after the GDE underpass, you can see an expanse of grassland or paddock, usually with a few cattle grazing, and sometimes a bunch of parked cars in the far distance. The grassland is Crace Nature Reserve, entered via a locked gate at the corner of Bellenden St and Hoskins St, Mitchell, beside the track to the model aero-club (the reason for the parked cars). The reserve is named ‘Crace’ because of the pointy rocky hill you see from the roads – 'Crace Hill' – though the suburb called Crace is several kilometres north of here. 

At 1.30 on Friday 13 July, on one of Canberra’s beautiful winter days (brilliant sunshine and not too much wind) four of us turned up to join Sarah Sharp at the gate. This FOG activity had been postponed to today from the previous Friday at 1.30 when (if you remember) it had been raining with a bitterly cold strong wind. 

Sarah drove us into our target site, which was about 1 km from the gate, where we disembarked to walk through very nice quality grassland. There was a wide range of forb species (Vittadinia, Velleia, Cryptandra, Lemon Beauty Heads, Lomandra, for example) as well as Kangaroo Grass Themeda triandra and a few other grass species, and cryptogams and bare soil – a perfect mix …. and, of course, the ‘rampaging’ Rutidosis that gave Sarah this activity’s title! (There are almost no flowers on these forbs at this time of year; by contrast, it should be very colourful in spring.) 

 Cryptandra amara, 15-20 cm tall. 

Cryptandra amara, closer. 

A cryptogam (moss), rather dry + Velleia paradoxa.

Velleia paradoxa Spurred Velleia (uncommon).

Sarah explained that she had originally discovered this good patch of Rutidosis leptorhynchoides (Button Wrinklewort) in 1998 during discussions about managing the area for conservation. The Button Wrinklewort was in an erosion scald, and the plants at that time had been thoroughly grazed. 

To protect this threatened species, the population was fenced off (from cattle but not roos) and allowed to regenerate. Since then it has spread considerably. The number of plants is estimated or counted periodically: 150 counted in 1998; 1000 and 4000 estimated in 1999 and 2000; 200–1000 estimated in 2016/17.

We five agreed to count the number of plants for 2018. 

 Sarah and Lorraine counting.... (Note Crace Hill in the distance.)

The plants range from small bushes, up to 25 cm or so across, to tiny seedlings (but completely recognisable) 1–2 cm across. Necessarily, our counts were not accurate, but our tally was over 3000 plants – the population has not shrunk after all! 

 If you zoom in, you can see spectacles (near bottom left, to give scale) and both seedling and bushy Rutidosis leptorhynchoides.

How nice to be able to congratulate the land managers on their conservation. This particular patch is not grazed except by roos – cattle merely pass through it when moving between the surrounding paddocks which they graze for conservation and fire-control. Sarah said that Serrated Tussock, Chilean Needlegrass and African Lovegrass are deliberately controlled in the reserve as a whole, and we could see there had been recent spraying of weed grasses; they were all near the entry gate.

Sarah also told us there has been some recent genomic work on this population of Button Wrinklewort to see if it will be suitable as a donor population to genetically rescue smaller populations. If its vigour is anything to go by, it will certainly be suitable! 

Thank you Sarah. What an interesting and different activity – nice to feel one is doing something useful while enjoying such a glorious winter’s day.

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* This is adapted from my original draft account of the day, with small amendments and additional plant names provided by Sarah Sharp. I expect to publish a shorter version of this account in the FOG newsletter in late August (News of Friends of Grasslands, September-October 2018). That version is likely (space permitting) to include extra information Sarah has added, and photos by Andy Russell. The photos in this blog post are only mine.